• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The journal of physical chemistry, A. Molecules, spectroscopy, kinetics, environment, & general theory >Theoretical Chemical Kinetic Study of the H-Atom Abstraction Reactions from Aldehydes and Acids by (H)over dot Atoms and (H)over dot , H (O)over dot (2), and CH3 Radicals
【24h】

Theoretical Chemical Kinetic Study of the H-Atom Abstraction Reactions from Aldehydes and Acids by (H)over dot Atoms and (H)over dot , H (O)over dot (2), and CH3 Radicals

机译：通过<（H）原子>和<（H）原子>，H <（O）原子>（2）和CH3自由基从醛与酸进行H-原子抽象反应的理论化学动力学研究

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

We have performed a systematic, theoretical chemical kinetic investigation of H atom abstraction by H atoms and OH, HO2, and CH3 radicals from aldehydes (methanal, ethanal, propanal, and isobutanal) and acids (methanoic acid, ethanoic acid, propanoic acid, and isobutanoic acid). The geometry optimizations and frequencies of all of the species in the reaction mechanisms of the title reactions were calculated using the MP2 method and the 6-311G(d,p) basis set. The one-dimensional hindered rotor treatment for reactants and transition states and the intrinsic reaction coordinate calculations were also determined at the MP2/6-311G(d,p) level of theory. For the reactions of methanal and methanoic acid with H atoms and OH, HO2, and CH3 radicals, the calculated relative electronic energies were obtained with the CCSD(T)/cc-pVXZ (where X = D, T, and Q) method and were extrapolated to the complete basis set limit. The electronic energies obtained with the CCSD(T)/cc-pVTZ method were benchmarked against the CCSD(T)/CBS energies and were found to be within 1 kcal mol(-1) of one another. Thus, the energies calculated using the less expensive CCSD(T)/cc-pVTZ method were used in all of the reaction mechanisms and in calculating our high-pressure limit rate constants for the title reactions. Rate constants were calculated using conventional transition state theory with an asymmetric Eckart tunneling correction, as implemented in Variflex. Herein, we report the individual and average rate constants, on a per H atom basis, and total rate constants in the temperature range 500-2000 K. We have compared some of our rate constant results to available experimental and theoretical data, and our results are generally in good agreement.
机译：我们已经进行了系统的，理论上的化学动力学研究，研究了H原子以及醛（甲烷，乙醛，丙醛和异丁醛）和酸（甲烷酸，乙醇酸，丙酸和异丁酸）。使用MP2方法和6-311G（d，p）基础集计算标题反应反应机理中所有物质的几何优化和频率。还以MP2 / 6-311G（d，p）的理论水平确定了反应物和过渡态的一维受阻转子处理以及本征反应坐标计算。对于甲烷酸和甲烷酸与H原子以及OH，HO2和CH3自由基的反应，使用CCSD（T）/ cc-pVXZ（其中X = D，T和Q）方法获得了计算出的相对电子能，推断到完整的基准集限制。通过CCSD（T）/ cc-pVTZ方法获得的电子能量相对于CCSD（T）/ CBS能量进行了基准测试，发现彼此之间在1 kcal mol（-1）之内。因此，使用较便宜的CCSD（T）/ cc-pVTZ方法计算的能量用于所有反应机理中，并用于计算标题反应的高压极限速率常数。速率常数是使用Variflex中实现的具有非对称Eckart隧道校正的传统过渡状态理论计算得出的。在此，我们报告了每个H原子的单个和平均速率常数，以及在500-2000 K温度范围内的总速率常数。我们将一些速率常数结果与可用的实验和理论数据进行了比较，并得出了结果总体上都很好。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号